9,9-Dimethyl-9-silafluorene.

The title compound, C(14)H(14)Si, crystallizes with two almost identical mol-ecules (r.m.s. deviation = 0.080 Å for all non-H atoms) in the asymmetric unit. All atoms of the silafluorene moiety lie in a common plane (r.m.s. deviations = 0.049 and 0.035 Å for the two mol-ecules in the asymmetric unit). The Si-C(meth-yl) bonds are significantly shorter [1.865 (4)-1.868 (4) Å] than the Si-C(aromatic) bonds [1.882 (3)-1.892 (3) Å]. Owing to strain in the five-membered ring, the endocyclic C-Si-C angles are reduced to 91.05 (14) and 91.21 (14)°.

Related literature

For the synthesis, see: Hudrlik et al. (2006 ▶). For related compounds, see: Kaufmann et al. (2008 ▶).

Experimental

Crystal data

C14H14Si

M = 210.34

Monoclinic,

a = 16.1336 (8) Å

b = 8.7752 (5) Å

c = 17.0227 (11) Å

β = 92.208 (5)°

V = 2408.2 (2) Å3

Z = 8

Mo Kα radiation

μ = 0.16 mm−1

T = 173 (2) K

0.22 × 0.17 × 0.09 mm

Data collection

Stoe IPDS-II two-circle diffractometer

Absorption correction: multi-scan (MULABS; Spek, 2003 ▶; Blessing, 1995 ▶) T min = 0.966, T max = 0.976

38382 measured reflections

4404 independent reflections

3274 reflections with I > 2σ(I)

R int = 0.082

Refinement

R[F 2 > 2σ(F 2)] = 0.061

wR(F 2) = 0.157

S = 1.12

4404 reflections

271 parameters

H-atom parameters constrained

Δρmax = 0.38 e Å−3

Δρmin = −0.29 e Å−3

Data collection: X-AREA (Stoe & Cie, 2001 ▶); cell refinement: X-AREA; data reduction: X-AREA; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: XP in SHELXTL-Plus (Sheldrick, 2008 ▶); software used to prepare material for publication: SHELXL97 and PLATON (Spek, 2003 ▶).

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809003614/at2718sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536809003614/at2718Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

C14H14Si	F(000) = 896
Mr = 210.34	Dx = 1.160 Mg m−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 18030 reflections
a = 16.1336 (8) Å	θ = 2.4–27.5°
b = 8.7752 (5) Å	µ = 0.16 mm−1
c = 17.0227 (11) Å	T = 173 K
β = 92.208 (5)°	Plate, colourless
V = 2408.2 (2) Å3	0.22 × 0.17 × 0.09 mm
Z = 8

Stoe IPDS-II two-circle diffractometer	4404 independent reflections
Radiation source: fine-focus sealed tube	3274 reflections with I > 2σ(I)
graphite	Rint = 0.082
ω scans	θmax = 25.4°, θmin = 2.4°
Absorption correction: multi-scan (MULABS; Spek, 2003; Blessing, 1995)	h = −19→19
Tmin = 0.966, Tmax = 0.976	k = −10→10
38382 measured reflections	l = −20→20

Refinement on F2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F2 > 2σ(F2)] = 0.061	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.157	H-atom parameters constrained
S = 1.12	w = 1/[σ2(Fo2) + (0.0668P)2 + 1.3736P] where P = (Fo2 + 2Fc2)/3
4404 reflections	(Δ/σ)max < 0.001
271 parameters	Δρmax = 0.38 e Å−3
0 restraints	Δρmin = −0.29 e Å−3

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

	x	y	z	Uiso*/Ueq
Si1A	0.04143 (6)	0.84574 (10)	0.17553 (5)	0.0343 (2)
C1A	0.09531 (19)	0.8679 (4)	0.27489 (19)	0.0346 (7)
C2A	0.15535 (19)	0.9860 (4)	0.27160 (19)	0.0336 (7)
C3A	0.2043 (2)	1.0224 (4)	0.3386 (2)	0.0428 (8)
H3A	0.2449	1.1007	0.3365	0.051*
C4A	0.1936 (3)	0.9439 (5)	0.4081 (2)	0.0515 (10)
H4A	0.2274	0.9681	0.4534	0.062*
C5A	0.1342 (3)	0.8308 (5)	0.4124 (2)	0.0515 (10)
H5A	0.1272	0.7782	0.4605	0.062*
C6A	0.0847 (2)	0.7941 (4)	0.3465 (2)	0.0439 (8)
H6A	0.0433	0.7178	0.3501	0.053*
C7A	0.0576 (2)	0.6583 (4)	0.1269 (2)	0.0466 (9)
H7A1	0.1172	0.6368	0.1256	0.070*
H7A2	0.0339	0.6616	0.0730	0.070*
H7A3	0.0303	0.5780	0.1563	0.070*
C8A	−0.0723 (2)	0.8848 (4)	0.1776 (2)	0.0458 (9)
H8A1	−0.0813	0.9832	0.2032	0.069*
H8A2	−0.0993	0.8040	0.2070	0.069*
H8A3	−0.0958	0.8878	0.1237	0.069*
C11A	0.10420 (19)	1.0065 (4)	0.13428 (19)	0.0326 (7)
C12A	0.15905 (18)	1.0648 (4)	0.19395 (19)	0.0321 (7)
C13A	0.2105 (2)	1.1889 (4)	0.1784 (2)	0.0408 (8)
H13A	0.2475	1.2273	0.2184	0.049*
C14A	0.2074 (2)	1.2558 (4)	0.1047 (2)	0.0467 (9)
H14A	0.2415	1.3412	0.0947	0.056*
C15A	0.1546 (2)	1.1985 (4)	0.0452 (2)	0.0441 (9)
H15A	0.1532	1.2442	−0.0054	0.053*
C16A	0.1037 (2)	1.0741 (4)	0.0600 (2)	0.0387 (8)
H16A	0.0683	1.0348	0.0190	0.046*
Si1	0.46279 (5)	0.38341 (10)	0.17151 (5)	0.0319 (2)
C1	0.40267 (19)	0.4048 (4)	0.26355 (19)	0.0328 (7)
C2	0.34203 (18)	0.5214 (4)	0.25218 (19)	0.0319 (7)
C3	0.2873 (2)	0.5548 (4)	0.3116 (2)	0.0396 (8)
H3	0.2464	0.6318	0.3037	0.048*
C4	0.2928 (2)	0.4752 (5)	0.3820 (2)	0.0458 (9)
H4	0.2551	0.4971	0.4219	0.055*
C5	0.3532 (3)	0.3635 (4)	0.3947 (2)	0.0488 (9)
H5	0.3569	0.3104	0.4433	0.059*
C6	0.4083 (2)	0.3298 (4)	0.3358 (2)	0.0418 (8)
H6	0.4501	0.2549	0.3451	0.050*
C7	0.5764 (2)	0.4193 (4)	0.1862 (2)	0.0420 (8)
H7A	0.5852	0.5171	0.2130	0.063*
H7B	0.6022	0.4222	0.1351	0.063*
H7C	0.6015	0.3375	0.2183	0.063*
C8	0.4471 (2)	0.1964 (4)	0.1206 (2)	0.0432 (8)
H8A	0.3876	0.1767	0.1126	0.065*
H8B	0.4724	0.1151	0.1529	0.065*
H8C	0.4732	0.1994	0.0695	0.065*
C11	0.40308 (18)	0.5457 (4)	0.12296 (18)	0.0312 (7)
C12	0.34395 (18)	0.6015 (4)	0.17523 (18)	0.0297 (7)
C13	0.2947 (2)	0.7273 (4)	0.1539 (2)	0.0383 (8)
H13	0.2552	0.7648	0.1890	0.046*
C14	0.3034 (2)	0.7970 (4)	0.0819 (2)	0.0431 (8)
H14	0.2698	0.8824	0.0679	0.052*
C15	0.3610 (2)	0.7436 (4)	0.0297 (2)	0.0463 (9)
H15	0.3670	0.7922	−0.0196	0.056*
C16	0.4098 (2)	0.6178 (4)	0.0506 (2)	0.0414 (8)
H16	0.4485	0.5803	0.0147	0.050*

	U11	U22	U33	U12	U13	U23
Si1A	0.0323 (5)	0.0327 (5)	0.0383 (5)	−0.0072 (4)	0.0058 (3)	−0.0003 (4)
C1A	0.0344 (16)	0.0312 (17)	0.0390 (18)	0.0049 (14)	0.0098 (13)	−0.0021 (14)
C2A	0.0286 (16)	0.0329 (17)	0.0395 (18)	0.0051 (13)	0.0035 (13)	−0.0057 (14)
C3A	0.0374 (18)	0.044 (2)	0.046 (2)	0.0087 (15)	−0.0037 (15)	−0.0084 (16)
C4A	0.064 (2)	0.055 (2)	0.035 (2)	0.018 (2)	−0.0069 (17)	−0.0116 (17)
C5A	0.068 (3)	0.053 (2)	0.0334 (19)	0.018 (2)	0.0061 (17)	0.0028 (16)
C6A	0.052 (2)	0.041 (2)	0.0398 (19)	0.0095 (16)	0.0133 (16)	0.0001 (15)
C7A	0.055 (2)	0.041 (2)	0.045 (2)	−0.0138 (17)	0.0127 (16)	−0.0058 (16)
C8A	0.0376 (18)	0.047 (2)	0.053 (2)	−0.0107 (16)	0.0045 (15)	0.0038 (17)
C11A	0.0283 (16)	0.0328 (17)	0.0370 (17)	−0.0029 (13)	0.0057 (13)	−0.0016 (13)
C12A	0.0223 (14)	0.0317 (17)	0.0424 (18)	0.0010 (12)	0.0036 (12)	−0.0069 (14)
C13A	0.0348 (18)	0.039 (2)	0.049 (2)	−0.0062 (14)	0.0047 (15)	−0.0071 (16)
C14A	0.0388 (19)	0.039 (2)	0.063 (2)	−0.0138 (16)	0.0102 (16)	0.0006 (18)
C15A	0.045 (2)	0.045 (2)	0.042 (2)	−0.0076 (16)	0.0103 (15)	0.0062 (16)
C16A	0.0334 (17)	0.044 (2)	0.0388 (18)	−0.0071 (15)	0.0023 (14)	−0.0011 (15)
Si1	0.0305 (4)	0.0289 (5)	0.0362 (5)	0.0054 (4)	−0.0002 (3)	0.0007 (4)
C1	0.0345 (16)	0.0283 (16)	0.0352 (17)	−0.0044 (13)	−0.0035 (13)	−0.0021 (13)
C2	0.0264 (15)	0.0319 (17)	0.0372 (17)	−0.0055 (13)	−0.0018 (12)	−0.0062 (13)
C3	0.0367 (18)	0.044 (2)	0.0389 (19)	−0.0070 (15)	0.0050 (14)	−0.0105 (15)
C4	0.047 (2)	0.056 (2)	0.0352 (19)	−0.0149 (18)	0.0078 (15)	−0.0107 (17)
C5	0.065 (2)	0.049 (2)	0.0327 (18)	−0.0198 (19)	0.0001 (16)	0.0003 (16)
C6	0.049 (2)	0.039 (2)	0.0379 (19)	−0.0090 (16)	−0.0025 (15)	0.0006 (15)
C7	0.0319 (17)	0.039 (2)	0.055 (2)	0.0053 (14)	−0.0033 (15)	0.0023 (16)
C8	0.047 (2)	0.0363 (19)	0.046 (2)	0.0047 (16)	0.0006 (16)	−0.0024 (15)
C11	0.0278 (15)	0.0296 (16)	0.0362 (17)	0.0029 (13)	−0.0001 (12)	−0.0014 (13)
C12	0.0266 (14)	0.0306 (16)	0.0317 (16)	0.0007 (13)	−0.0014 (12)	−0.0068 (13)
C13	0.0303 (17)	0.041 (2)	0.0438 (19)	0.0093 (14)	−0.0010 (14)	−0.0065 (15)
C14	0.0413 (19)	0.041 (2)	0.046 (2)	0.0183 (16)	−0.0054 (15)	−0.0008 (16)
C15	0.050 (2)	0.051 (2)	0.0377 (19)	0.0160 (17)	−0.0006 (15)	0.0059 (16)
C16	0.0404 (18)	0.048 (2)	0.0363 (18)	0.0161 (16)	0.0052 (14)	0.0047 (15)

Si1A—C7A	1.865 (4)	Si1—C7	1.867 (3)
Si1A—C8A	1.868 (4)	Si1—C8	1.868 (4)
Si1A—C1A	1.882 (3)	Si1—C1	1.884 (3)
Si1A—C11A	1.887 (3)	Si1—C11	1.892 (3)
C1A—C6A	1.396 (5)	C1—C6	1.396 (5)
C1A—C2A	1.421 (5)	C1—C2	1.424 (4)
C2A—C3A	1.399 (5)	C2—C3	1.399 (5)
C2A—C12A	1.495 (5)	C2—C12	1.488 (4)
C3A—C4A	1.386 (5)	C3—C4	1.387 (5)
C3A—H3A	0.9500	C3—H3	0.9500
C4A—C5A	1.384 (6)	C4—C5	1.393 (6)
C4A—H4A	0.9500	C4—H4	0.9500
C5A—C6A	1.389 (5)	C5—C6	1.396 (5)
C5A—H5A	0.9500	C5—H5	0.9500
C6A—H6A	0.9500	C6—H6	0.9500
C7A—H7A1	0.9800	C7—H7A	0.9800
C7A—H7A2	0.9800	C7—H7B	0.9800
C7A—H7A3	0.9800	C7—H7C	0.9800
C8A—H8A1	0.9800	C8—H8A	0.9800
C8A—H8A2	0.9800	C8—H8B	0.9800
C8A—H8A3	0.9800	C8—H8C	0.9800
C11A—C16A	1.396 (5)	C11—C16	1.392 (5)
C11A—C12A	1.417 (4)	C11—C12	1.417 (4)
C12A—C13A	1.401 (5)	C12—C13	1.399 (4)
C13A—C14A	1.383 (5)	C13—C14	1.381 (5)
C13A—H13A	0.9500	C13—H13	0.9500
C14A—C15A	1.392 (5)	C14—C15	1.391 (5)
C14A—H14A	0.9500	C14—H14	0.9500
C15A—C16A	1.395 (5)	C15—C16	1.394 (5)
C15A—H15A	0.9500	C15—H15	0.9500
C16A—H16A	0.9500	C16—H16	0.9500
C7A—Si1A—C8A	108.95 (18)	C7—Si1—C8	108.96 (17)
C7A—Si1A—C1A	115.01 (17)	C7—Si1—C1	113.95 (16)
C8A—Si1A—C1A	112.61 (16)	C8—Si1—C1	114.13 (16)
C7A—Si1A—C11A	114.04 (15)	C7—Si1—C11	114.35 (15)
C8A—Si1A—C11A	114.28 (16)	C8—Si1—C11	113.64 (15)
C1A—Si1A—C11A	91.21 (14)	C1—Si1—C11	91.05 (14)
C6A—C1A—C2A	118.6 (3)	C6—C1—C2	118.7 (3)
C6A—C1A—Si1A	132.0 (3)	C6—C1—Si1	131.9 (3)
C2A—C1A—Si1A	109.4 (2)	C2—C1—Si1	109.4 (2)
C3A—C2A—C1A	119.9 (3)	C3—C2—C1	120.1 (3)
C3A—C2A—C12A	125.1 (3)	C3—C2—C12	124.9 (3)
C1A—C2A—C12A	115.0 (3)	C1—C2—C12	114.9 (3)
C4A—C3A—C2A	119.8 (4)	C4—C3—C2	119.8 (3)
C4A—C3A—H3A	120.1	C4—C3—H3	120.1
C2A—C3A—H3A	120.1	C2—C3—H3	120.1
C5A—C4A—C3A	120.7 (3)	C3—C4—C5	120.7 (3)
C5A—C4A—H4A	119.6	C3—C4—H4	119.7
C3A—C4A—H4A	119.6	C5—C4—H4	119.7
C4A—C5A—C6A	120.1 (4)	C4—C5—C6	119.9 (3)
C4A—C5A—H5A	120.0	C4—C5—H5	120.0
C6A—C5A—H5A	120.0	C6—C5—H5	120.0
C5A—C6A—C1A	120.8 (4)	C1—C6—C5	120.7 (4)
C5A—C6A—H6A	119.6	C1—C6—H6	119.7
C1A—C6A—H6A	119.6	C5—C6—H6	119.7
Si1A—C7A—H7A1	109.5	Si1—C7—H7A	109.5
Si1A—C7A—H7A2	109.5	Si1—C7—H7B	109.5
H7A1—C7A—H7A2	109.5	H7A—C7—H7B	109.5
Si1A—C7A—H7A3	109.5	Si1—C7—H7C	109.5
H7A1—C7A—H7A3	109.5	H7A—C7—H7C	109.5
H7A2—C7A—H7A3	109.5	H7B—C7—H7C	109.5
Si1A—C8A—H8A1	109.5	Si1—C8—H8A	109.5
Si1A—C8A—H8A2	109.5	Si1—C8—H8B	109.5
H8A1—C8A—H8A2	109.5	H8A—C8—H8B	109.5
Si1A—C8A—H8A3	109.5	Si1—C8—H8C	109.5
H8A1—C8A—H8A3	109.5	H8A—C8—H8C	109.5
H8A2—C8A—H8A3	109.5	H8B—C8—H8C	109.5
C16A—C11A—C12A	118.5 (3)	C16—C11—C12	118.4 (3)
C16A—C11A—Si1A	132.1 (2)	C16—C11—Si1	132.3 (2)
C12A—C11A—Si1A	109.4 (2)	C12—C11—Si1	109.3 (2)
C13A—C12A—C11A	120.2 (3)	C13—C12—C11	119.9 (3)
C13A—C12A—C2A	124.8 (3)	C13—C12—C2	124.8 (3)
C11A—C12A—C2A	114.9 (3)	C11—C12—C2	115.3 (3)
C14A—C13A—C12A	120.0 (3)	C14—C13—C12	120.3 (3)
C14A—C13A—H13A	120.0	C14—C13—H13	119.9
C12A—C13A—H13A	120.0	C12—C13—H13	119.9
C13A—C14A—C15A	120.4 (3)	C13—C14—C15	120.7 (3)
C13A—C14A—H14A	119.8	C13—C14—H14	119.7
C15A—C14A—H14A	119.8	C15—C14—H14	119.7
C14A—C15A—C16A	119.9 (3)	C14—C15—C16	119.2 (3)
C14A—C15A—H15A	120.0	C14—C15—H15	120.4
C16A—C15A—H15A	120.0	C16—C15—H15	120.4
C15A—C16A—C11A	120.9 (3)	C11—C16—C15	121.6 (3)
C15A—C16A—H16A	119.5	C11—C16—H16	119.2
C11A—C16A—H16A	119.5	C15—C16—H16	119.2
C7A—Si1A—C1A—C6A	−65.4 (4)	C7—Si1—C1—C6	−60.0 (4)
C8A—Si1A—C1A—C6A	60.2 (4)	C8—Si1—C1—C6	66.1 (3)
C11A—Si1A—C1A—C6A	177.2 (3)	C11—Si1—C1—C6	−177.3 (3)
C7A—Si1A—C1A—C2A	116.2 (2)	C7—Si1—C1—C2	119.8 (2)
C8A—Si1A—C1A—C2A	−118.1 (2)	C8—Si1—C1—C2	−114.2 (2)
C11A—Si1A—C1A—C2A	−1.1 (2)	C11—Si1—C1—C2	2.4 (2)
C6A—C1A—C2A—C3A	2.2 (5)	C6—C1—C2—C3	−2.6 (4)
Si1A—C1A—C2A—C3A	−179.2 (2)	Si1—C1—C2—C3	177.6 (2)
C6A—C1A—C2A—C12A	−176.6 (3)	C6—C1—C2—C12	176.4 (3)
Si1A—C1A—C2A—C12A	2.0 (3)	Si1—C1—C2—C12	−3.4 (3)
C1A—C2A—C3A—C4A	−0.5 (5)	C1—C2—C3—C4	0.7 (5)
C12A—C2A—C3A—C4A	178.1 (3)	C12—C2—C3—C4	−178.1 (3)
C2A—C3A—C4A—C5A	−0.7 (5)	C2—C3—C4—C5	0.9 (5)
C3A—C4A—C5A—C6A	0.3 (6)	C3—C4—C5—C6	−0.7 (5)
C4A—C5A—C6A—C1A	1.4 (5)	C2—C1—C6—C5	2.8 (5)
C2A—C1A—C6A—C5A	−2.6 (5)	Si1—C1—C6—C5	−177.5 (3)
Si1A—C1A—C6A—C5A	179.2 (3)	C4—C5—C6—C1	−1.2 (5)
C7A—Si1A—C11A—C16A	63.3 (4)	C7—Si1—C11—C16	59.2 (4)
C8A—Si1A—C11A—C16A	−62.9 (4)	C8—Si1—C11—C16	−66.7 (4)
C1A—Si1A—C11A—C16A	−178.5 (3)	C1—Si1—C11—C16	176.2 (3)
C7A—Si1A—C11A—C12A	−118.2 (2)	C7—Si1—C11—C12	−117.9 (2)
C8A—Si1A—C11A—C12A	115.5 (2)	C8—Si1—C11—C12	116.1 (2)
C1A—Si1A—C11A—C12A	0.0 (2)	C1—Si1—C11—C12	−0.9 (2)
C16A—C11A—C12A—C13A	0.9 (5)	C16—C11—C12—C13	−0.7 (5)
Si1A—C11A—C12A—C13A	−177.8 (2)	Si1—C11—C12—C13	176.9 (2)
C16A—C11A—C12A—C2A	179.9 (3)	C16—C11—C12—C2	−178.4 (3)
Si1A—C11A—C12A—C2A	1.2 (3)	Si1—C11—C12—C2	−0.8 (3)
C3A—C2A—C12A—C13A	−1.9 (5)	C3—C2—C12—C13	4.2 (5)
C1A—C2A—C12A—C13A	176.8 (3)	C1—C2—C12—C13	−174.7 (3)
C3A—C2A—C12A—C11A	179.1 (3)	C3—C2—C12—C11	−178.2 (3)
C1A—C2A—C12A—C11A	−2.2 (4)	C1—C2—C12—C11	2.8 (4)
C11A—C12A—C13A—C14A	0.5 (5)	C11—C12—C13—C14	0.1 (5)
C2A—C12A—C13A—C14A	−178.4 (3)	C2—C12—C13—C14	177.6 (3)
C12A—C13A—C14A—C15A	−1.3 (5)	C12—C13—C14—C15	0.1 (5)
C13A—C14A—C15A—C16A	0.7 (6)	C13—C14—C15—C16	0.3 (6)
C14A—C15A—C16A—C11A	0.7 (5)	C12—C11—C16—C15	1.1 (5)
C12A—C11A—C16A—C15A	−1.5 (5)	Si1—C11—C16—C15	−175.9 (3)
Si1A—C11A—C16A—C15A	176.8 (3)	C14—C15—C16—C11	−0.9 (6)